Member
class Member @InternalWowApi constructor(val service: String, val node: String, val address: String, val expiresAt: Long, val groups: Set<String> = emptySet())
node is a live member of service until expiresAt (epoch milliseconds, exclusive), serving the lease groups: a node records its membership once per service, not once per lease group, and the groups it takes part in are a field of that one record. address is the node's internal address (host:port of its internal port, never the public one): where the cluster channel reaches it, so commands can be routed to the owners of partitions.
service keys the record: a service's node membership, or a narrower set keyed the same way, such as the nodes of one state revision, whose records list no groups.
Fields may be added: construct one with of; the constructor is internal to Wow.